Trailer adapter question

I'm upgrading my boat trailer to Disc brakes. This requires the installation of a solenoid valve in the trailer hydraulic line, which cuts the disk brakes out during reversing. For the cut-out, apparently the back-up light circuit is used. The adapter I got with the 02 4WD Duramax is a four pin unit, one for ground, which worked well on the drum brakes.
My question is, will a 7 to 5-pin adapter like the "Hoppy" p/n 47375 sold by after marked work?

My boat is in Mexico and I would like have the right part before I drive down.

Have you already done any upgrading for the hydraulic brakes?

I have upgraded my TT to hydraulic disc brakes. I used the HD3000 hydraulic disc brake system from Tow Brake, www.towbrake.com, 877-927-6778. They sell the unit as a do-it-yourself unit, with all necessary parts. This system stops my 12K TT almost in the same distance as stoping with my truck alone. I love the security I feel knowing I can stop as fast as I need. The people at Tow Brake are great to deal with, very responsive and helpful.

Rocinante, I ordered the Disc brakes from Southwest Wheel Co., www.southwestwheel.com
Since Disc brakes require a higher hydraulic pressure and I'm not sure what actuator I have for a possible upgrade of the master cylinder, I ordered an Atwood actuator, P/N A888740, which is made for Disc brakes, but presently on back-order. The installation doesn't seem to be a big issue.

Sounds like you are already into this system too far to change directions. The system I have has the actuator and all included and I use the Prodigy brake controler I already had. I can't help you with piecing together a system, as mine came complete, sorry.

Tow Brake said that one problem they had to solve was how to make the hydraulic brake system operate smoothly using standard current brake controlers. They seem to have gotten the solution right, as the trailer brakes operate smoothly both foward and reverse.

To answer your question, yes, the 7-5 hoppy adapter will work. I ran into the same situation with my new boat trailer and used the same adapter. 18 bucks in NAPA. Hope this helps.

Thanks RONKDMAX, this is what I wanted to know!